A known fluorescence endoscope device in the related art can obtain a bright fluorescence image of a diseased site by irradiating an observation target site doped with a fluorochrome that preferentially accumulates in a diseased site, such as a cancer cell, with excitation light for exciting the fluorochrome to generate drug fluorescence and by capturing an image of the drug fluorescence (for example, see PTL 1). The fluorescence endoscope device disclosed in PTL 1 corrects variations in fluorescence intensity of a fluorescence image, which depends on the observation distance, the observation angle, etc., by dividing a fluorescence image, which is obtained from an observation target site irradiated with excitation light and is based on the fluorescence intensity, by a reference image, which is obtained from the same observation target site irradiated with reference light and is based on the intensity of the reflected light, to obtain a quantitative divided fluorescence image.